Location-based configuration of a load control device

ABSTRACT

A method of automatically programming a new load control device that replaces an old load control device takes advantage of a remote identification tag (e.g., an RFID tag) located in the vicinity of the old device. The remote identification tag stores an identifier that is representative of a location in which the old device is installed. The method includes the steps of: (1) storing a setting of an old device in a memory of a controller; (2) associating the setting with the identifier of the old device in the memory of the controller; (3) the new device retrieving the identifier from the remote identification tag after the new device is installed in the location of the old device; (4) the new device transmitting the identifier to the controller; and (5) the controller transmitting the setting of the old device to the new device in response to receiving the identifier.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of commonly-assigned U.S.patent application Ser. No. 16/556,344, filed on Aug. 30, 2019, which isa continuation of commonly-assigned U.S. patent application Ser. No.15/959,355, filed on Apr. 23, 2018, now U.S. Pat. No. 10,405,411, issuedon which is a continuation of commonly-assigned U.S. patent applicationSer. No. 15/332,395, filed on Oct. 24, 2016, now U.S. Pat. No.10,129,962, issued Nov. 13, 2018, which is a continuation ofcommonly-assigned U.S. patent application Ser. No. 14/274,109, filed May9, 2014, now U.S. Pat. No. 9,516,724, issued Dec. 6, 2016, which is acontinuation of commonly-assigned U.S. patent application Ser. No.12/718,273, filed Mar. 5, 2010, now U.S. Pat. No. 8,760,262, issued Jun.24, 2014, which is a non-provisional application of commonly-assignedU.S. Provisional Application Ser. No. 61/162,018, filed Mar. 20, 2009,the entire disclosures of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to load control systems for controllingthe amount of power delivered to one or more electrical loads and,specifically, to a method of automatically programming a new loadcontrol device, such as an electronic dimming ballast, using a remoteidentification tag, such as a radio-frequency identification (RFID)transponder that is associated with the location (e.g., fixture) inwhich the new load control device is installed.

Description of the Related Art

A typical prior art load control system is operable to control theamount of power delivered to an electrical load, such as a lighting loador a motor load, from an alternating-current (AC) power source. Alighting control system generally comprises a plurality of controldevices coupled to a communication link to allow for communicationbetween the control devices. The control devices of a typical lightingcontrol system include lighting control devices (e.g., dimmer circuitsor electronic dimming ballasts) operable to control the amount of powerdelivered to the lighting loads (and thus, the intensity of the lightingloads) in response to digital messages received via the communicationlink. In addition, the control devices of a typical lighting controlsystem often include one or more keypad devices that transmit commandsvia the communication link in order to control the loads coupled to thelighting control devices.

Lighting control systems for fluorescent lamps typically comprise acontroller and a plurality of electronic dimming ballasts that areoperable to communicate via a digital communication link. The controllermay communicate with the ballasts using, for example, theindustry-standard Digital Addressable Lighting Interface (DALI)communication protocol. The DALI protocol allows each ballast in thelighting control system to be assigned a unique digital address, to beprogrammed with configuration information (e.g., preset lightingintensities), and to control a fluorescent lamp in response to commandstransmitted via the communication link. Some controllers may provide auser interface that allows for control of the lighting control system.The controllers of a lighting control system may comprise, for example,wall-mounted keypads or handheld devices, such as infrared (IR) remotecontrols, personal digital assistants (PDA). The IR commands arereceived by an IR receiving sensor that is operable to send appropriatecommands to the controlled ballasts. In addition to IR receivingsensors, the lighting control system may also include daylight sensorsor occupancy sensors. The daylight and occupancy sensors are operable tomonitor the condition (e.g., the ambient light level or motion from anoccupant, respectively) of a space and send appropriate commands to thecontrolled ballasts in response to the sensed conditions in the space.

When the multi-ballast lighting control system is initially installed,each ballast must be configured appropriately. For example, a ballastmay be configured to be included in a particular group with otherballasts that are responsive to commands received from a particular IRreceiver. That ballast may also be configured to be included in anotherparticular group of ballasts that are responsive to commands receivedfrom a particular daylight sensor, or an additional group of ballastsresponsive to a particular occupancy sensor. All ballasts within aparticular group are operable to be controlled together. In addition,the ballast may be further configured with certain individual operatingparameters, such as minimum and maximum light intensity parameters. Inorder to maintain these configurations, one of the controllers of themulti-ballast lighting control system (e.g., a central processor) isoperable to store and update these configurations as needed.

In the event that an existing ballast within the control system fails,the failed ballast must be replaced with a new ballast. Theconfigurations that were associated with the failed ballast must then bereassigned to the new replacement ballast such that the new ballast willoperate in the same fashion as the failed ballast had operated. Forexample, if the failed ballast had been configured to operate in aparticular group of ballasts responsive to an occupancy sensor, then thenew ballast, once installed in the same location as the failed ballast,must also be configured to operate in the same ballast group responsiveto the occupancy sensor.

One prior art method of reconfiguring a new replacement ballastcomprises using a hand-held PDA to run a ballast replacement program inwhich the user enters the unique serial number of the failed ballast andthe unique serial number of the new replacement ballast. The PDA cantransmit these serial numbers to an IR receiver within the lightingcontrol system. Once these serial numbers are received by the centralprocessor via the communication link, the central processor can updatethe configurations accordingly such that the new ballast will operate inthe same groups and with the same individual operating parameters as thefailed ballast. This prior method of reconfiguration is described ingreater detail in commonly-assigned U.S. Pat. No. 7,391,297, issued Jun.24, 2008, entitled HANDHELD PROGRAMMING FOR A LIGHTING CONTROL SYSTEM,the entire disclosure of which is hereby incorporated by reference.

The prior art method of reconfiguration can be tedious as the user mustinput the serial numbers of both the failed and new ballasts. If manyballasts are to be replaced in the lighting control system, the priorart method becomes even more tedious as more serial numbers must beentered. Thus, there exists a need for a method of automatic ballastreplacement and reconfiguration that does not require the user tocompletely re-program a new ballast or to enter any serial numbers.

SUMMARY OF THE INVENTION

According to the present invention, a method of automaticallyprogramming a new load control device that replaces an old load controldevice of a load control system takes advantage of a remoteidentification tag located in the vicinity of the old load controldevice. The remote identification tag stores an identifier that isrepresentative of a location in which the old load control device isinstalled. The method comprises the steps of: (1) storing a setting ofan old load control device in a memory of a controller; (2) associatingthe identifier with the setting of the old load control device in thememory of the controller; (3) the new load control device retrieving theidentifier from the remote identification tag after the new load controldevice is installed in the location of the old load control device; (4)the new load control device transmitting the identifier to thecontroller; and (5) the controller transmitting the setting of the oldload control device to the new load control device in response toreceiving the identifier.

In addition, a load control device for controlling the power deliveredfrom an AC power source to an electrical load is also described herein.The load control device comprises a load control circuit adapted to becoupled between the AC power source and the electrical load, acontroller operatively coupled to the load control circuit forcontrolling the power delivered to the load, a communication circuitadapted to be coupled to a communication link, and an identifierretrieval circuit coupled to the controller. The communication circuitallows the controller to transmit and receive digital messages on thecommunication link. The identifier retrieval circuit retrieves anidentifier from a remote identification tag located in the vicinity ofthe load control device. The load control device is operable to transmita digital message including the identifier on the communication link,and to subsequently receive a digital message including a load controlsetting associated with the identifier. For example, the identifierretrieval circuit may comprise a RFID circuit for retrieving theidentifier from an RFID tag located in the vicinity of the load controldevice. In addition, the load control device may be adapted to bemounted to a fixture in which the remote identification tag is located.

According to another embodiment of the present invention, a load controlsystem comprises a load control device installed in the vicinity of aremote identification tag for storing an identifier and a controllercoupled to the load control device via a communication link. The loadcontrol device is operable to retrieve the identifier from the remoteidentification tag. The controller is operable to store in a memory aload control setting, which is associated with the identifier of theremote identification tag. The load control device is operable totransmit the identifier to the controller, and the controller isoperable to transmit the load control setting associated with theidentifier to the load control device in response to receiving theidentifier.

Other features and advantages of the present invention will becomeapparent from the following description of the invention that refers tothe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in greater detail in the followingdetailed description with reference to the drawings in which:

FIG. 1 is a simplified block diagram of a fluorescent lighting controlsystem having a digital ballast controller and a plurality of ballastsfor control of the intensity of a plurality of fluorescent lampsaccording to a first embodiment of the present invention;

FIG. 2 is a simplified block diagram of the digital ballast controllerof the load control system of FIG. 1;

FIG. 3 is a simplified block diagram of one of the digital electronicdimming ballasts of the fluorescent lighting control system of FIG. 1according to the first embodiment;

FIG. 4 is a simplified flowchart of a startup procedure executed atstartup by each of the ballasts of the fluorescent lighting controlsystem of FIG. 1;

FIG. 5 is a simplified flowchart of an automatic ballast replacementprocedure executed by the controller of the fluorescent lighting controlsystem of FIG. 1;

FIG. 6 is a simplified block diagram of an electronic dimming ballastaccording to a second embodiment of the present invention; and

FIG. 7 is a simplified block diagram of an electronic dimming ballastaccording to a third embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The foregoing summary, as well as the following detailed description ofthe preferred embodiments, is better understood when read in conjunctionwith the appended drawings. For the purposes of illustrating theinvention, there is shown in the drawings an embodiment that ispresently preferred, in which like numerals represent similar partsthroughout the several views of the drawings, it being understood,however, that the invention is not limited to the specific methods andinstrumentalities disclosed.

FIG. 1 is a simplified block diagram of a fluorescent lighting controlsystem 100 for control of the intensities of a plurality of fluorescentlamps 114, 124, 134 according to a first embodiment of the presentinvention. The fluorescent lighting control system 100 includes aplurality of lighting fixtures 110, 120, 130 (e.g., three fixtures) inwhich the lamps 114, 124, 134 are located. Each fixture 110, 120, 130also includes a respective digital electronic dimming ballast 112, 122,132 that is coupled to the respective lamp 114, 124, 134 via a lampwiring 116, 126, 136. The ballasts 112, 122, 132 are each coupled to analternating-current (AC) power source (not shown) via a line voltagewiring 104 for receiving an AC mains line voltage. The lighting controlsystem 100 further comprises a digital ballast controller 102 that iscoupled to each of the ballasts 112, 122, 132 via a digital ballastcommunication link 106. Accordingly, the ballasts 112, 122, 132 areoperable to control the intensities of the lamps 114, 124, 134 inresponse to digital messages received from the digital ballastcontroller 102 via the digital ballast communication link 106.

The digital ballast controller 102 also operates as a link power supply.Specifically, the digital ballast controller 102 receives the AC mainsline voltage and generates a DC link voltage for the digital ballastcommunication link 106. The digital ballast controller 102 and ballasts112, 122, 132 are operable to transmit and receive digital messages viathe digital ballast communication link 106 using, for example, thedigital addressable lighting interface (DALI) protocol. The digitalballast communication link 106 may be coupled to more ballasts 112, 122,132, for example, up to 64 ballasts. The ballasts 112, 122, 132 are allassigned a unique serial number (e.g., a 64-bit serial number) duringmanufacture of the ballast. The serial number is used to identify theballasts 112, 122, 132 during configuration of the ballasts after theballasts are installed. The ballasts 112, 122, 132 are then assigned ashort address during configuration. Because the short address requiresless communication bandwidth than the serial number (e.g., 8 bits), theshort address is used to transmit and receive digital messages on thecommunication link 106, such that the digital message may be transmittedmore quickly, thus improving the overall response speed of the lightingcontrol system 100.

During configuration of the lighting control system 100, the ballasts112, 122, 132 may be assigned the short addresses and may be configuredwith one or more configuration settings (i.e., load control settings),such as, for example, high-end trims, low-end trims, preset intensities,fade times, and ballast groups. The digital ballast controller 102 isoperable to build a database of the short addresses and theconfiguration settings of the ballasts 112, 122, 132 during theconfiguration of the lighting control system 100. An example of aconfiguration procedure for the lighting control system 100 is describedin greater detail in commonly-assigned U.S. patent application Ser. No.11/870,783, filed Oct. 11, 2007, entitled METHOD OF BUILDING A DATABASEOF A LIGHTING CONTROL SYSTEM, the entire disclosure of which is herebyincorporated by reference.

While not shown in FIG. 1, each ballast 112, 122, 132 may also beoperable to receive a plurality of inputs from, for example, anoccupancy sensor, an infrared (IR) receiver, and a keypad, and tosubsequently transmit digital messages or control the intensities of therespective lamp 114, 124, 134 in response. An example of a ballast thatis able to be coupled to a communication link and to receive inputs fromvarious sensors and other external devices is described in greaterdetail in commonly-assigned U.S. Pat. No. 7,369,060, issued May 6, 2008,entitled DISTRIBUTED INTELLIGENCE BALLAST SYSTEM AND EXTENDED LIGHTINGCONTROL PROTOCOL, and U.S. Pat. No. 7,619,539, issued Nov. 17, 2009,entitled MULTIPLE-INPUT ELECTRONIC BALLAST WITH PROCESSOR, the entiredisclosures of which are hereby incorporated by reference.

The ballasts 112, 122, 132 are each located within the vicinity of aremote identification tag (e.g., a passive RFID tag or transponder 118,128, 138). As shown in FIG. 1, the RFID tags 118, 128, 138 may belocated within the respective lighting fixtures 110, 120, 130. Forexample, each RFID tags 118, 128, 138 may comprise a label that ispermanently affixed to the inside of the respective fixture 110, 120,130, for example, during initial installation of the fixture, or duringinstallation of the ballast into the fixture. The ballasts 112, 122, 132are each operable to generate an electronic field that allowsradio-frequency (RF) signals 108 (i.e., RFID signals) to be transmittedto power and activate the RFID tags 118, 128, 138. In response to theRFID signals 108, each RFID tag 118, 128, 138 is operable to transmit aunique RFID identifier (i.e., a fixture identifier) to the respectiveballast 112, 122, 132. The RFID identifier may be, for example, a 64-bitserial number that is unique to the specific lighting fixture 110, 120,130 in which the RFID tag 118, 128, 138 is installed. In the event thatone of the ballasts 112, 122, 132 fails and a new replacement ballast isinstalled in its place, the RFID identifier of the RFID tag 118, 128,138 of the fixture 110, 120, 130 (in which the new ballast is installed)is used by the digital ballast controller 102 to program thenewly-installed ballast, as will be described in greater detail below.Alternatively, the ballasts 112, 122, 132 could be mounted to junctionboxes (not shown) located outside of the fixtures 110, 120, 130, and theRFID tags 118, 128, 138 could each be mounted to the outside of thefixtures or to the junction boxes (but only within the range of the RFsignals 108 generated by the ballasts 112, 122, 132).

FIG. 2 is a simplified block diagram of the digital ballast controller102 of the fluorescent lighting control system 100. The digital ballastcontroller 120 comprises a rectifier 210 for receiving the AC linevoltage and for generating a rectified voltage. A link voltage powersupply circuit 220 receives the rectified voltage and generates the DClink voltage W_(LINK) (i.e., approximately 18 V_(DC)) for the digitalballast communication link 106. A microcontroller 230 is coupled to amemory 236 for storage of the database of addresses and configurationsettings, and to a wired communication circuit 234 for transmitting andreceiving digital messages on the digital ballast communication link106. The microcontroller 230 may alternatively comprise, for example, aprogrammable logic device (PLD), a microprocessor, an applicationspecific integrated circuit (ASIC), or any suitable type of controlleror control circuit. A low-voltage power supply 232 is connected acrossthe outputs of the rectifier 210 to provide a DC supply voltage V_(CC1)(e.g., 5 V), which is used to power the microcontroller 230 and otherlow-voltage circuitry of the digital ballast controller 102.

FIG. 3 is a simplified block diagram of one of the digital electronicdimming ballasts 112 according to the first embodiment of the presentinvention. The electronic ballast 112 comprises a hot terminal H and aneutral terminal N for receipt of the AC mains line voltage, and a loadcontrol circuit having a front end circuit 310 and a back end circuit320. The front end circuit 310 includes an EMI (electromagneticinterference) filter and rectifier circuit 330 for minimizing the noiseprovided on the AC mains (i.e., at the hot terminal H and the neutralterminal N) and for generating a rectified voltage from the AC mainsline voltage. The front end circuit 310 further comprises a boostconverter 340 for generating a direct-current (DC) bus voltage V_(BUS)across a bus capacitor C_(BUS). The DC bus voltage V_(BUS) typically hasa magnitude (e.g., 465 V) that is greater than the peak voltage V_(PK)of the AC mains line voltage (e.g., 170 V). The boost converter 340 alsooperates as a power-factor correction (PFC) circuit for improving thepower factor of the ballast 112. The boost converter 340 may comprise,for example, a PFC integrated circuit (not shown), such as, for example,part number TDA4863 manufactured by Infineon Technologies AG.Alternatively, the ballast 112 may not comprise the boost converter 340,such that the DC bus voltage V_(BUS) has a maximum magnitude equal toapproximately the peak voltage V_(PK) of the AC mains line voltage.

The back end circuit 320 includes an inverter circuit 350 for convertingthe DC bus voltage V_(BUS) to a high-frequency AC voltage. The invertercircuit 350 comprises one or more semiconductor switches, for example,two FETs (not shown), and a ballast control integrated circuit (notshown) for controlling the FETs. The ballast control integrated circuitis operable to selectively render the FETs conductive to control theintensity of the lamps 114. The ballast control integrated circuit maycomprise, for example, part number NCP5111 manufactured by OnSemiconductor. The back end circuit 320 further includes an outputcircuit 360 comprising a resonant tank circuit for coupling thehigh-frequency AC voltage generated by the inverter circuit 350 to thefilaments of the lamps 114.

A microcontroller 370 is coupled to the inverter circuit 350 for controlof the switching of the FETs to thus turn the lamps 114 on and off andto control (i.e., dim) the intensity of the lamps 114 between a minimumintensity (e.g., 1%) and a maximum intensity (e.g., 100%). Themicrocontroller 370 may alternatively comprise, for example, aprogrammable logic device (PLD), a microprocessor, an applicationspecific integrated circuit (ASIC), or any suitable type of controlleror control circuit. The ballast 112 further comprises a power supply 372for generating a supply voltage V_(CC2) (e.g., approximately 5 V) forpowering the microcontroller 370 and other low-voltage circuitry of theballast. A wired communication circuit 374 is coupled to themicrocontroller 370 and allows the ballast 112 to communicate with theother ballasts on the digital ballast communication link 106. Themicrocontroller 370 is further coupled to a memory 376 for storing theballast serial number, the short address, the RFID identifier, and theother configuration settings. Examples of digital electronic ballastsare described in greater detail in commonly-assigned U.S. Pat. No.7,489,090, issued Feb. 10, 2009, entitled ELECTRONIC BALLAST HAVINGADAPTIVE FREQUENCY SHIFTING; U.S. Pat. No. 7,528,554, issued May 5,2009, entitled ELECTRONIC BALLAST HAVING A BOOST CONVERTER WITH ANIMPROVED RANGE OF OUTPUT POWER; and U.S. patent application Ser. No.11/787,934, filed Apr. 18, 2007, entitled COMMUNICATION CIRCUIT FOR ADIGITAL ELECTRONIC DIMMING BALLAST; the entire disclosures of which arehereby incorporated by reference.

The ballast 112 further comprises an identifier retrieval circuit (e.g.,an RFID circuit 390), which is operable to generate the electronic fieldthat allows the RF signals 108 to be transmitted to power and activatethe RFID tag 118. The microcontroller 370 is operable to receive theRFID identifier from the RFID tag 118 via the RFID circuit 390. Thecommunication range of the RFID circuit 390 is sized such that only theRFID tag 118 in the fixture 110 in which the ballast 112 is installed isresponsive to the RF signals 108 transmitted by the RFID circuit.Examples of RFID circuits are shown and described in greater detail inU.S. Pat. No. 6,282,407, issued Aug. 28, 2001, entitled ACTIVEELECTROSTATIC TRANSMITTER AND COMMUNICATING SYSTEM, and U.S. Pat. No.6,362,738, issued Mar. 26, 2002, entitled READER FOR USE IN A RADIOFREQUENCY IDENTIFICATION SYSTEM AND METHOD THEREOF, the entiredisclosures of which are hereby incorporated by reference.

After each ballast 112, 122, 132 is assigned a short address during theconfiguration of the lighting control system 100, the ballasts may beprogrammed with additional configuration settings, (e.g., high-end trim,low-end trim, preset intensities, fade times, and ballast groups) whichare stored in the memory 376 of the ballasts and in a memory 236 of thedigital ballast controller 102. During configuration, the ballasts 112,122, 132 also transmit the RFID identifiers of the respective RFID tags118, 128, 138 to the digital ballast controller 102, such that thedigital ballast controller is operable to correlate the RFID identifierswith the respective short addresses and other configuration settings ofeach ballast in the memory 236 of the digital ballast controller.

When one of the ballasts 112, 122, 132 is replaced by a new replacementballast, the new replacement ballast is operable to retrieve the RFIDidentifier from the respective RFID tag 118, 128, 138 at startup. Thedigital ballast controller 102 periodically transmits query messages forunaddressed ballasts on the digital ballast communication link 106. Inresponse to the query message, the new replacement ballast (which doesnot have a short address) transmits a digital message to the digitalballast controller including the RFID identifier from the respectiveRFID tag 118, 128, 138. The digital ballast controller 102 then assignsthe short address that corresponds to the received RFID identifier tothe newly-installed ballast. The digital ballast controller 102 furtherprograms the new replacement ballast with the configuration settingsassociated with the received RFID identifier in the memory 236. Sincethe RFID tags 118, 128, 138 are permanently affixed to the fixtures 110,120, 130 and cannot be removed from the fixtures, the RFID tags clearlylink the configuration settings of the ballast 112, 122, 132 to eachfixture in which the ballast is installed.

FIG. 4 is a simplified flowchart of a startup procedure 400 that isexecuted by the microcontroller 370 of each ballast 112, 122, 132 whenthe controller first starts up (i.e., powers up) at step 410. If theballast has already been assigned a short address (i.e., there is ashort address stored in the memory 376) at step 412, the ballast simplyoperates in normal mode at step 414 and the startup procedure 400 exits.If the ballast has not been assigned a short address (i.e., the ballastis a replacement ballast) at step 412, the microcontroller 370 causesthe RFID circuit 390 to transmit an RFID signal to the respective RFIDtag 118, 128, 138 at step 416. The microcontroller 370 then waits untila response is received from the respective RFID tag 118, 128, 138 atstep 418 or a timeout (e.g., 100 milliseconds) expires at step 420. Ifthe timeout expires at step 420 before the response is received at step418, the ballast begins to operate in an “out-of-box” (i.e., a default)mode at step 422 and the startup procedure 400 exits. On the other hand,if a response is received at step 418 before the timeout expires at step420, the microcontroller 370 stores the received RFID identifier in thememory 376 at step 424 and the ballast operates in the out-of-box modeat step 422, before the startup procedure 400 exits.

FIG. 5 is a simplified flowchart of an automatic ballast replacementprocedure 500 executed periodically (e.g., once every one to fiveminutes) by the controller 230 of the digital ballast controller 102.The controller 230 first transmits a query message for all unaddressedballasts on the digital ballast communication link 106 at step 510. Ifthe controller 230 does not receive any responses at step 512, theautomatic ballast replacement procedure 500 simply exits. However, ifthe controller 230 receives a response at step 512, but the responsedoes not contain an RFID identifier at step 514 (i.e., the lightingfixture in which the unaddressed ballast is installed does not includean RFID tag), the controller assigns a new short address to the ballastusing the serial number of the ballast at step 516, and then transmitsanother query message for all unaddressed ballasts on the digitalballast communication link 106 at step 510. For example, at step 516,the controller 230 may use a conventional address assignment procedureas described in previously-referenced U.S. patent application Ser. No.11/870,783. The controller 230 must ensure that no more than one ballastis assigned each unique short address.

If the response contains an RFID identifier at step 514, but the RFIDidentifier is not stored in the memory 236 of the digital ballastcontroller 102 at step 518 (i.e., the lighting fixture in which theaddressed ballast is installed is new), the controller 230 transmits anew short address to the ballast at step 520. The controller 230 thenstores the received RFID identifier and the new short address in thememory 236 of the digital ballast controller 102 at step 522 andtransmits another query message for all unaddressed ballasts on thedigital ballast communication link 106 at step 510. If the received RFIDidentifier is stored in the memory 236 of the digital ballast controller102 at step 518, the controller 230 transmits the short address that isassociated with the RFID identifier in the memory to the respondingballast at step 524. The controller 230 then transmits the configurationsettings that are associated with the RFID identifier in the memory 236to the ballast at step 526 and transmits another query message for allunaddressed ballasts on the digital ballast communication link 106 atstep 510. When there are no more unaddressed ballasts at step 512, theautomatic ballast replacement procedure 500 exits.

While the present application has been described with reference to thepassive RFID tags 118, 128, 138, the concepts of the present inventioncould also be applied to systems having active RFID tags, for example,powered from the AC line voltage or from a battery. In addition, theRFID tags 118, 128, 138 could alternatively be implemented by othertypes of remote identification devices, such as, for example, a barcode. FIG. 6 is a simplified block diagram of an electronic dimmingballast 612 having a bar code reader 690 according to a secondembodiment of the present invention. The ballast 612 has many similarfunctional blocks as the ballast 112 of the first embodiment (as shownin FIG. 3). According to the second embodiment, a unique bar code (thatserves as a fixture identifier) may be located on the fixture in whichthe ballast 612 is mounted at a location at which the bar code reader690 of the ballast can retrieve the fixture identifier from the barcode. For example, the bar code may be located on a label 692 affixed toa sidewall 694 of the fixture, and the ballast 612 may be mounted withthe bar code reader immediately adjacent to and directed towards thelabel 692 having the bar code. At start up, a microcontroller 670 causesthe bar code reader 690 to read the bar code to retrieve the fixtureidentifier, transmits a digital message including the fixture identifierto the digital ballast controller 102, and subsequently receives one ormore digital messages including the configuration settings of theballast 612.

FIG. 7 is a simplified block diagram of an electronic dimming ballast712 that is operable to retrieve a fixture identifier from a remoteidentification tag 800 according to a third embodiment of the presentinvention. The ballast 712 of the third embodiment includes many similarfunctional blocks as the ballast 112 of the first embodiment (as shownin FIG. 3). The remote identification tag 800 is coupled to the linevoltage wiring 104 (FIG. 1) that is connected to the hot and neutralterminals H, N of the ballast 712, such that the remote identificationtag is coupled in series between the AC power source and the ballast.Since the remote identification tag 800 remains coupled to the linevoltage wiring 104 even when the ballast 712 is removed from thecircuit, the remote identification tag is permanently located in thefixture. Accordingly, the remote identification tag 800 clearly linksthe configuration settings of the ballast 712 to the fixture in whichthe remote identification tag is installed.

The ballast 712 and the remote identification tag 800 are operable tocommunicate with each other via the line voltage wiring 104, e.g., usingpower-line carrier (PLC) communication, to allow for retrieval of thefixture identifier. Specifically, the ballast 712 and the remoteidentification tag 800 comprise respective microcontrollers 770, 870 andrespective PLC communication circuits 790, 890 that are coupled torespective communication transformers 792, 892. In addition, the remoteidentification tag 800 comprises a filter circuit 894 in the form of acapacitor C_(F), which is coupled such that a communication loop isformed through the current transformers 792, 892 and an input capacitorC_(IN) (or other capacitance) of the ballast 712. The remoteidentification tag 800 further comprises a memory 896 for storing thefixture identifier and a power supply 898 for generating a low-voltagesupply voltage V_(DD) for powering the microcontroller 870 and otherlow-voltage circuitry of the remote identification tag. An example of aload control system that includes control devices having communicationtransformers for PLC communication is described in greater detail incommonly-assigned U.S. patent application Ser. No. 11/447,431, filedJun. 6, 2006, entitled SYSTEM FOR CONTROL OF LIGHTS AND MOTORS, theentire disclosure of which is hereby incorporated by reference.

The microcontrollers 770, 870 are operable to excite the communicationtransformers 792, 892 to modulate high-frequency signals onto the linevoltage wiring 104 to thus transmit digital messages. Specifically, ifthe ballast 712 does not have a short address at startup, themicrocontroller 770 transmits a digital message including a fixtureidentifier request to the remote identification tag 800 via the linevoltage wiring 104. The microcontroller 870 of the remote identificationtag 800 subsequently transmits a digital message including the fixtureidentifier stored in the memory 896 to the ballast 712. The capacitorC_(F) prevents digital messages transmitted by the microcontroller 770of the ballast 712 or the microcontroller 810 of the remoteidentification tag 800 from being received by any of the other controldevices that are also coupled to the AC mains line voltage. In otherwords, the digital messages transmitted by the ballast 712 are onlyreceived by the remote identification tag 800, and the digital messagestransmitted by the remote identification tag are only received by theballast. After retrieving the fixture identifier from the remoteidentification tag 800, the microcontroller 770 of the ballast 712 isoperable to transmit a digital message including the fixture identifierto the digital ballast controller 102 via the digital ballastcommunication link 106, and to subsequently receive one or more digitalmessages including the configuration settings from the digital ballastcontroller.

Accordingly, the present invention provides a fully automatic procedurefor replacing an old programmable ballast with a new programmableballast. As detailed above, the new ballast is automatically programmedwith the configuration settings of the old ballast after the new ballastis installed. No additional programming steps or user inputs arerequired. Since the procedure of the present invention is fullyautomatic, a person not skilled to perform ballast programmingprocedures is able to replace the old programmable ballast with the newprogrammable ballast as if the new ballast were a prior art conventionalnon-programmable ballast.

While the present invention has been described with reference to theballasts 112, 612, 712, the concepts of the present invention could beapplied to other types of load control devices, such as, for example,light-emitting diode (LED) drivers for LED lighting loads, electronicswitches, motor or fan speed control devices, motorized windowtreatments, or dimmer circuits for other types of lighting loads, suchas, incandescent lamps, compact fluorescent lamps, magnetic low-voltage(MLV) lighting loads, and electronic low-voltage (ELV) lighting loads.

Although the present invention has been described in relation toparticular embodiments thereof, many other variations and modificationsand other uses will become apparent to those skilled in the art. It ispreferred, therefore, that the present invention be limited not by thespecific disclosure herein, but only by the appended claims.

What is claimed is:
 1. An apparatus comprising: a lighting load; a load control circuit configured to control power delivered from a power source to the lighting load; a controller configured to control the load control circuit to adjust the power delivered to the lighting load; a first communication circuit communicatively coupled to the controller and adapted to be coupled to a communication link n enable the controller to transmit and receive messages via the communication link; and an identifier-retrieval circuit communicatively coupled to the controller; wherein, when the apparatus is mounted in close proximity to an identifier-transmitting device, the controller is configured to receive, via the identifier-retrieval circuit, an identifier from the identifier-transmitting device located in a fixture in which the apparatus is installed, the identifier received from the identifier-transmitting device representative of a location of the identifier-transmitting device; and wherein the controller is further configured to transmit a first message including the identifier on the communication link via the first communication circuit, and to subsequently receive a second message including a load control setting associated with the identifier via the first communication circuit.
 2. The apparatus of claim 1, wherein the load control circuit is adapted to be coupled between the power source and the lighting load and comprises a back end circuit configured to control an amount of power delivered to the lighting load to control an intensity of the lighting load.
 3. The apparatus of claim 2, wherein the load control circuit comprises a front end circuit configured to receive an alternating-current line voltage and generate a direct-current bus voltage that is received by the back end circuit.
 4. The apparatus of claim 3, wherein the front end circuit comprises a boost converter circuit configured to generate the bus voltage.
 5. The apparatus of claim 4, wherein the boost converter circuit operates as a power factor correction circuit to improve the power factor of the apparatus.
 6. The apparatus of claim 4, wherein the bus voltage has a magnitude greater than a peak magnitude of the alternating-current line voltage.
 7. The apparatus of claim 3, wherein the front end circuit comprises a rectifier circuit.
 8. The apparatus of claim 7, wherein the bus voltage has a magnitude equal to approximately a peak magnitude of the alternating-current line voltage.
 9. The apparatus of claim 3, further comprising: a hot terminal and a neutral terminal for receiving the alternating-current line voltage; wherein the front end circuit comprises an electromagnetic interference filter for minimizing noise provided at the hot and neutral terminals.
 10. The apparatus of claim 1, wherein the identifier-retrieval circuit comprises a second communication circuit configured to receive a third message including the identifier from the identifier-transmitting device.
 11. The apparatus of claim 10, wherein, prior to receiving the third message including the identifier via the second communication circuit, the controller is configured to transmit a fourth message to the identifier-transmitting device via the second communication circuit of the identifier retrieval circuit.
 12. The apparatus of claim 11, wherein the controller is configured to automatically transmit the fourth message when the controller is not assigned a short address at power up of the apparatus.
 13. The apparatus of claim 1, wherein, after transmitting the first message including the identifier on the communication link via the first communication circuit, the controller is configured to receive a short address associated with the identifier via the first communication circuit.
 14. The apparatus of claim 13, wherein the controller is configured to use the short address to transmit and receive messages via the communication link.
 15. The apparatus of claim 13, wherein the controller is configured to operate in a default mode after storing the identifier in the memory.
 16. The apparatus of claim 1, further comprising: a memory coupled to the controller for storing the identifier; wherein the controller is configured to store the identifier received from the identifier-transmitting device in the memory.
 17. The apparatus of claim 16, wherein the controller is configured to store the identifier received from the identifier-transmitting device in the memory when the controller is not assigned a short address at power up of the apparatus.
 18. The apparatus of claim 1, wherein the controller is configured to receive a plurality of messages including a plurality of respective load control settings associated with the identifier.
 19. The apparatus of claim 1, wherein the lighting load comprises an LED lighting load, and the apparatus comprises an LED driver for controlling an intensity of the LED lighting load.
 20. The apparatus of claim 1, wherein the control setting comprises one of a high-end trim, a low-end trim, a fade time, and a group of the apparatus. 